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Keyword: dendrochronology

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  • New Technique Provides Accurate Dating of Ancient Skeletons

    06/21/2018 4:09:31 PM PDT · by SunkenCiv · 22 replies
    Eurekalert ^ | June 17, 2018 | European Society of Human Genetics
    Interest in the origins of human populations and their migration routes has increased greatly in recent years. A critical aspect of tracing migration events is dating them. However, the radiocarbon techniques*, that are commonly used to date and analyse DNA from ancient skeletons can be inaccurate and not always possible to apply. Inspired by the Geographic Population Structure model that can track mutations in DNA that are associated with geography, researchers have developed a new analytic method, the Time Population Structure (TPS), that uses mutations to predict time in order to date the ancient DNA. Dr Umberto Esposito... TPS can...
  • Study: Radiocarbon Dating Inaccurate in the Holy Land

    The analysis was made by comparing Jordanian juniper trees that grew between roughly 1600 and 1910 A.D., according to the researchers... The researchers results indicated that, like in many other parts of the globe, the growing season fluctuates enough to tilt the results. Thus, the traditional Carbon-14 calibration curve for the Northern Hemisphere is not entirely accurate for southern Jordan, Israel and Egypt. The offset averages about 19 years, the researchers said... The paper contends that massive timeline restructuring could be in the offing, for events both major and minor. “Although, overall, the Carbon-14 offset identified here produces what may...
  • Unusual climate during Roman times plunged Eurasia into hunger and disease

    04/15/2018 6:41:17 AM PDT · by SunkenCiv · 50 replies
    Science News ^ | April 11, 2018 | University of Helsinki
    A recent study indicates that volcanic eruptions in the mid 500s resulted in an unusually gloomy and cold period. A joint research project of the Chronology Laboratory of the Finnish Museum of Natural History and Natural Resources Institute Finland (Luke) suggests that the years 536 and 541-544 CE were very difficult... An extended period of little light may make it difficult for humans to survive. The level of production of plants is dependent on the amount of available sunlight. Food production, i.e, farming and animal husbandry, rely on the same solar energy. Humans, meanwhile, become more prone to disease if...
  • Did Abraham Lincoln sleep here?

    02/11/2018 11:40:26 AM PST · by bgill · 34 replies
    cbs ^ | Feb. 11, 2018 | cbs
    Visitors to a small log cabin in Kentucky are right to ask: Is it true that Abraham Lincoln slept here? On the eve of Lincoln's 209th birthday tomorrow, Brook Silva-Braga has the answer... "What we're trying to do is authenticate when this cabin was made by using the tree rings in the logs," he replied. Some say our 16th president, born in these hills in 1809, spent some of his childhood in this cabin at Knob Creek. But did he?... So no, Abraham Lincoln did not sleep here in the Knob Creek cabin … or in the "symbolic cabin" at...
  • Over A Thousand Years Ago, The Sun Exploded — And Changed Life On Earth Forever

    11/16/2015 7:03:45 AM PST · by blam · 34 replies
    BI - Slate ^ | 11-16-2015 | Phil Plait
    Phil PlaitNovember 16, 2015 A new study says that violent space weather that could cost $2 trillion in damage is more common than previously thought In the years 774 and 993, the Earth was attacked from space. Not by aliens, but by a natural event—and it was very, very powerful. Whatever it was, it subtly altered the chemistry of our planet’s atmosphere, creating trace amounts of radioactive elements like chlorine-36, beryllium-10, and carbon-14. And those provide the clue to what the event was: Those isotopes are created when high-energy protons slam into our air. That means the source must have...
  • Sky 'Crucifix' in Ancient Text May Be Mystery-Solving Supernova

    07/01/2012 9:22:00 AM PDT · by SunkenCiv · 28 replies
    Livescience ^ | Friday, June 29, 2012 | Life's Little Mysteries Staff
    According to an Old English manuscript chronicling the history of the Anglo-Saxons, a mysterious "red crucifix" appeared in the "heavens" over Britain one evening in A.D. 774. Now astronomers say it may have been the supernova explosion that sprinkled unexplained traces of carbon-14 in tree rings that year, halfway around the world in Japan. Jonathon Allen, an undergraduate student at the University of California, Santa Cruz, made the connection this week after listening to a Nature podcast. He heard a team of Japanese scientists discussing new research in which they measured an odd spike in carbon-14 levels in tree rings...
  • 777-Year-Old Tree Is a Babe in Muir Woods (Tallest Tree AT Muir Woods Not 1500 Yrs Old, Study Shows)

    06/01/2015 7:22:29 PM PDT · by nickcarraway · 29 replies
    San Francisco Chronicle ^ | Monday, June 1, 2015 | Peter Fimrite
    The tallest redwood tree in Muir Woods — a giant that was assumed to have sprouted up to 1,500 years ago in the Middle Ages — is a measly 777 years old, a puerile sprig in the hallowed halls of old growth, an analysis of tree-ring data has revealed. The study, by a Humboldt State University scientist, is the first definitive determination of the age of trees in Muir Woods. The findings by Allyson Carroll, a tree-ring specialist, mean that a 249-foot-tall coast redwood known by the lackluster name of Tree 76 sprouted seven centuries later than originally believed, at...
  • Solar proton event seen in paleo records (Carbon 14 in Tree Rings)

    03/15/2013 7:37:13 AM PDT · by Ernest_at_the_Beach · 36 replies
    Watts Up With That? ^ | March 12, 2013 | Anthony Watts
    From the AGU weekly highlights: Large solar proton event explains 774-775 CE carbon-14 increase Tree ring records indicate that in 774-775 CE, atmospheric carbon-14 levels increased substantially. Researchers suggest that a solar proton event may have been the cause. In solar proton events, large numbers of high-energy protons are emitted from the Sun, along with other particles. If these particles reach EarthÂ’s atmosphere, they ionize the atmosphere and induce nuclear reactions that produce higher levels of carbon-14; the particles also cause chemical reactions that result in depletion of ozone in the ozone layer, allowing harmful ultraviolet radiation to reach the...
  • Researcher points to Sun as likely source of eighth-century 'Charlemagne event'

    12/12/2012 5:34:52 AM PST · by Renfield · 31 replies
    PhysOrg ^ | 11-20-2012
    (Phys.org)—Until recently, the years 774 and 775 were best known for Charlemagne's victory over the Lombards. But earlier this year, a team of scientists in Japan discovered a baffling spike in carbon-14 deposits within the rings of cedar trees that matched those same years. Because cosmic rays are tied to carbon-14 concentrations, scientists around the world have wondered about the cause: a nearby supernova, a gamma ray burst in the Milky Way or an intense superflare emanating from the Sun? Now, Adrian Melott, professor of physics and astronomy at the University of Kansas and Brian Thomas, KU alumnus and professor...
  • Mysterious radiation burst recorded in tree rings

    06/04/2012 10:58:45 AM PDT · by SunkenCiv · 46 replies
    Nature ^ | Sunday, June 3, 2012 | Richard A. Lovett
    Just over 1,200 years ago, the planet was hit by an extremely intense burst of high-energy radiation of unknown cause, scientists studying tree-ring data have found. The radiation burst, which seems to have hit between AD 774 and AD 775, was detected by looking at the amounts of the radioactive isotope carbon-14 in tree rings that formed during the AD 775 growing season in the Northern Hemisphere. The increase in 14C levels is so clear that the scientists, led by Fusa Miyake, a cosmic-ray physicist from Nagoya University in Japan, conclude that the atmospheric level of 14C must have jumped...
  • Archaeologists Rewrite Timeline Of Bronze And Iron Ages, Alphabet

    12/24/2001 5:04:31 AM PST · by blam · 21 replies · 613+ views
    Cornell University ^ | 12-19-2001 | Blaine P. Friedlander Jr.
    Archaeologists rewrite timeline of Bronze and Iron Ages, including early appearance of alphabet FOR RELEASE: Dec. 19, 2001 Contact: Blaine P. Friedlander Jr. Office: 607-255-3290 E-Mail: bpf2@cornell.edu ITHACA, N.Y. -- Using information gleaned from the sun's solar cycles and tree rings, archaeologists are rewriting the timeline of the Bronze and Iron Ages. The research dates certain artifacts of the ancient eastern Mediterranean decades earlier than previously thought. And it places an early appearance of the alphabet outside Phoenicia at around 740 B.C. Writing in two articles in the forthcoming issue of the journal Science (Dec. 21), archaeologists from Cornell University ...
  • Greek Island of Santorini Volcano Erupted in 16th Century

    03/22/2014 4:46:14 PM PDT · by SunkenCiv · 24 replies
    Greek Reporter ^ | March 8, 2014 | Abed Alloush
    According to a recent international study, the volcano of the island Santorini, Greece, erupted in the 16th century BC and not earlier. The survey characterized a number of research studies that took place in the past and have indicated that Santorini's volcano may have erupted a century earlier, as unreliable because the method based on tree-ring measurements that they used, could not provide them with accurate results. An international team of researchers led by Paolo Cherubini from the Swiss Federal Institute for Forest, Snow and Landscape Research (WSL) has demonstrated in the scientific journal Antiquity, that this method cannot provide...
  • Origins of Mysterious World Trade Center Ship Revealed

    07/29/2014 5:49:18 AM PDT · by the scotsman · 27 replies
    Yahoo UK News ^ | 29th July 2014 | Megan Gannon
    'In July 2010, amid the gargantuan rebuilding effort at the site of the World Trade Center in Lower Manhattan, construction workers halted the backhoes when they uncovered something unexpected just south of where the Twin Towers once stood. At 22 feet (6.7 meters) below today's street level, in a pit that would become an underground security and parking complex, excavators found the mangled skeleton of a long-forgotten wooden ship. Now, a new report finds that tree rings in those waterlogged ribs show the vessel was likely built in 1773, or soon after, in a small shipyard near Philadelphia. What's more,...
  • Ancient Tree (Almost) Older Than Dirt [ 5,000 to 30,000 years old ]

    12/23/2009 6:46:09 PM PST · by SunkenCiv · 24 replies · 2,458+ views
    Discovery ^ | Wednesday, December 23, 2009 | Michael Reilly
    The entire grove of trunks is in fact one plant, a newly discovered Palmer's oak (Quercus palmeri) that researchers estimate is over 13,000 years old, making it one of the oldest plants on Earth... none of its 70 stems get more than a few feet tall, and it grows in a boulder pile that doubles as shelter from the area's buffeting winds. At first glance, the scientists thought it was an isolated grove of trees, but something didn't add up: None of them produced fertile acorns, so the plants couldn't reproduce... Genetic analysis confirmed their suspicion. Each of the 70...
  • Ancient Volcano, Seeds And Treerings, Suggest Rewriting Late Bronze Age Mediterranean History (More)

    04/29/2006 12:24:20 PM PDT · by blam · 17 replies · 723+ views
    Cornell University ^ | 4-28-2006 | Alex Kwan
    April 28, 2006Cornell study of ancient volcano, seeds and tree rings, suggests rewriting Late Bronze Age Mediterranean history By Alex Kwan Separated in history by 100 years, the seafaring Minoans of Crete and the mercantile Canaanites of northern Egypt and the Levant (a large area of the Middle East) at the eastern end of the Mediterranean were never considered trading partners at the start of the Late Bronze Age. Until now. Trenchmaster Vronwy Hankey and foreman Antonis Zidianakis excavate storage jars from the Minoan settlement Myrtos-Pyrgos. The jars were analyzed in the Cornell study using radiocarbon analyses. Cultural links between...
  • ARCHAEOLOGY: New Carbon Dates Support Revised History of Ancient Mediterranean

    04/27/2006 4:59:30 PM PDT · by Lessismore · 77 replies · 2,583+ views
    Science Magazine ^ | 4/28/2006 | Michael Balter
    During the Late Bronze Age, the Aegean volcanic island of Thera erupted violently, spreading pumice and ash across the eastern Mediterranean and triggering frosts as far away as what is now California. The Theran town of Akrotiri was completely buried. Tsunamis up to 12 meters high crashed onto the shores of Crete, 110 kilometers to the south, and the cataclysm may ultimately have sped the demise of Crete's famed Minoan civilization. For nearly 30 years, archaeologists have fought over when the eruption took place. Those who rely on dates from pottery styles and Egyptian inscriptions put the event at roughly...
  • Olive branch solves a Bronze Age mystery

    04/28/2006 5:59:40 AM PDT · by The_Victor · 14 replies · 737+ views
    Yahoo/MSNBC (Science) ^ | 3:04 p.m. ET April 27, 2006 | Kathleen Wren
    WASHINGTON - Compared to the well-studied world of Homer’s Iliad and Odyssey, the civilizations that flourished in the eastern Mediterranean just before Homer’s time are still cloaked in mystery. Even the basic chronology of the region during this time has been heatedly debated. Now, a resolution has finally emerged -- initiated, quite literally, by an olive branch.Scientists have discovered the remains of a single olive tree, buried alive during a massive volcanic eruption during the Late Bronze Age. A study that dates this tree, plus another study that dates a series of objects from before, during and after the eruption,...
  • Wet climate may have fueled Mongol invasion

    07/20/2012 6:55:45 PM PDT · by rjbemsha · 43 replies
    NBC News ^ | July 20, 2012 | Stephanie Pappas
    Consistent rain and warm temperatures may have given the Mongols the energy source they needed to conquer Eurasia: grass for their horses (huge amount of grass needed to feed the 10 horses for each Mongol warrior).
  • UA scientists find evidence of Roman period megadrought (in US, not Rome)

    11/04/2011 4:02:52 PM PDT · by decimon · 20 replies
    University of Arizona ^ | November 4, 2011
    A new study at the University of Arizona's Laboratory of Tree-Ring Research has revealed a previously unknown multi-decade drought period in the second century A.D.Almost nine hundred years ago, in the mid-12th century, the southwestern U.S. was in the middle of a multi-decade megadrought. It was the most recent extended period of severe drought known for this region. But it was not the first. The second century A.D. saw an extended dry period of more than 100 years characterized by a multi-decade drought lasting nearly 50 years, says a new study from scientists at the University of Arizona. UA geoscientists...
  • Fall of Rome Recorded in Trees

    01/18/2011 10:49:18 PM PST · by neverdem · 38 replies
    ScienceNOW ^ | 13 January 2011 | Andrew Curry
    Enlarge Image Preserved. Climate changes recorded in tree rings correlate with important events in European history, such as the Black Death. Credit: Wikimedia When empires rise and fall and plagues sweep over the land, people have traditionally cursed the stars. But perhaps they should blame the weather. A new analysis of European tree-ring samples suggests that mild summers may have been the key to the rise of the Roman Empire—and that prolonged droughts, cold snaps, and other climate changes might have played a part in historical upheavals, from the barbarian invasions that brought about Rome's collapse to the Black...